Hot Butter was an instrumental cover band fronted by the keyboard player Stan Free. The other band members were Dave Mullaney, John Abbott, Bill Jerome, Steve Jerome, and Danny Jordan. The liner notes to the CD reissue do not indicate who played what, aside from Free at the Moog synthesizer. Indeed, the notes say the band was Free and "a bunch of fellow players". Based upon the photograph and the sound of the album, the group had two additional keyboardists, two percussionists, and a guitarist. They are best known for their 1972 cover of the Moog synthpop instrumental Popcorn, originally by Gershon Kingsley in 1969. Stan Free had previously played in Kinglsley's live moog prerformance ensemble and during their 1969 tour of the States they had used "Popcorn" as an encore. In 1972, remembering the positive response the song had received, Free released it as a single and it became a worldwide hit peaking at #5 in the UK and #9 in the US.